The New Zealand Plant Conservation Network

Species

Acrolejeunea pycnoclada var. pycnoclada

Common Name(s)

liverwort

Current Conservation Status

2009 - Data Deficient

Conservation status of New Zealand indigenous vascular plants, 2012
The conservation status of all known New Zealand vascular plant taxa at the rank of species and below were reassessed in 2012 using the New Zealand Threat Classification System (NZTCS). This report includes a statistical summary and brief notes on changes since 2009 and replaces all previous NZTCS lists for vascular plants. Authors: Peter J. de Lange, Jeremy R. Rolfe, Paul D. Champion, Shannel P. Courtney, Peter B. Heenan, John W. Barkla, Ewen K. Cameron, David A. Norton and Rodney A. Hitchmough. File size: 792KB

Qualifiers

2009 - DP, OL, SO

Authority

Acrolejeunea pycnoclada (Taylor) Schiffner var. pycnoclada

Family

Lejeuneaceae

Flora Category

Non Vascular - Native

Structural Class

Liverwort

Distribution

Indigenous. Kermadec Islands: Raoul Island

Habitat

The sole known gathering from Raoul Island came from the bark of a large Metrosideros kermadecensis overhanging the ephemeral watercourse that drains Sunshine Valley. Sunshine Valley is a major ravine/gorge system draining the south-eastern side of Raoul Island.

Features

Corticolous. Plant olive green in colour. Stems to 8 mm or more long, most shorter, appressed to bark. 0.3 mm (dry) to 0.9m m (wet) wide. Branches mostly of Lejeunea type but occasionally Frullania type. Stem diameter 90-110 µm, ventral merophyte of 4-5 cells in width, Cortical cells subrectangular to irregular in shape 20-30 x 12-22 µm, cortical cells c.17 surrounded by c.20 medullary cells. Leaves are imbricated when dry spreading but not becoming squarrose when wet. Lobe c.540 x 330 µm, broad, short crescent shaped with a rounded apex which is incurved. The dorsal base is not auriculate. The ventral margin is short and more or less recurved. The keel is curved, not decurrent and the cells not or weakly protuberant. Median leaf cells are ovoid 22 x 15-16 µm, base cells larger 29-31 x 16-17 µm, trigones are medium sized Y shaped (the sides swollen), intermediate thickenings scattered to scarce. Oilbodies were not present. Lobule is narrowly ovate rectangular with slightly oblique apex, the free margin is almost straight. Teeth (2-)3 each 1-2 cells long, erect, the first is at tip of the free margin, the hyaline papilla is at the base of the second tooth which is therefore the ‘apical tooth’, the lobule is about half the length of the lobe. Underleaf, in position slightly overlapping the base of the adjacent underleaf, broad oval in shape, about 320 µm wide and 190 µm long. The median cells ovoid 150-18 x 13-15 µm, slightly larger at base 22-25 x(9-)10-13. The rhizoid disc is small. Reproductive structures not present in the sole Kermadec gathering.

Flowering

Not seen

Fruiting

Not seen

Threats

First recognized from New Zealand in May 2011 from a single copious gathering made from Raoul Island, Sunshine Valley. The identity of the gathering was not known until the specimen was examined more closely in New Zealand, however despite the many liverworts collected from Raoul in May 2009 and May 2011 there were no further gatherings of this species evident, so it is likely that Acrolejeunea pycnoclada is very uncommon on Raoul Island. However, until a thorough survey for this inconspicuous plant is undertaken it is considered inappropriate to provide a more definitive threat listing.

Endemic Taxon

No

Endemic Genus

No

Endemic Family

No

This page last updated on 22 Aug 2013